This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. SPECIFIC AIMS: The Primary Objective is to estimate the proportion of participants undergoing solitary or repetitive percutaneous RFA treatment sessions whose livers have no identifiable tumor by CT scan at 18 months following initiation of therapy. The Secondary Objectives are to: -Explore the impact of solitary versus repetitive RFA on the primary objective; -Explore the impact of tumor size on the primary objective; -Evaluate for a possible correlation between the MELD Score and the primary objective; -Estimate the local and remote intrahepatic and extrahepatic tumor recurrence rates and their impact on the primary objective; -Explore the impact of tumor size on the local control rates; -Explore the impact of solitary or repetitive RFA with or without local/regional control the development of extra-hepatic tumor; -Estimate the local tumor eradication rate as determined by examination of whole liver specimens obtained via autopsy or explanation versus that determined by CT scan.